1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/* Copyright (C) 2003-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* Activate all C11 atomic builtins.
Note:
E.g. in nptl/pthread_key_delete.c if compiled with GCCs 6 and before,
an extra stack-frame is generated and the old value is stored on stack
before cs instruction but it never loads this value from stack.
An unreleased GCC 7 omit those stack operations.
E.g. in nptl/pthread_once.c the condition code of cs instruction is
evaluated by a sequence of ipm, sra, compare and jump instructions instead
of one conditional jump instruction. This also occurs with an unreleased
GCC 7.
The atomic_fetch_abc_def C11 builtins are now using load-and-abc instructions
on z196 zarch and higher cpus instead of a loop with compare-and-swap
instruction. */
#define USE_ATOMIC_COMPILER_BUILTINS 1
#ifdef __s390x__
# define __HAVE_64B_ATOMICS 1
#else
# define __HAVE_64B_ATOMICS 0
#endif
#define ATOMIC_EXCHANGE_USES_CAS 1
/* Implement some of the non-C11 atomic macros from include/atomic.h
with help of the C11 atomic builtins. The other non-C11 atomic macros
are using the macros defined here. */
/* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL.
Return the old *MEM value. */
#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg1_oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__atg1_oldval, \
newval, 1, __ATOMIC_ACQUIRE, \
__ATOMIC_RELAXED); \
__atg1_oldval; })
#define atomic_compare_and_exchange_val_rel(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg1_2_oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__atg1_2_oldval, \
newval, 1, __ATOMIC_RELEASE, \
__ATOMIC_RELAXED); \
__atg1_2_oldval; })
/* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL.
Return zero if *MEM was changed or non-zero if no exchange happened. */
#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
({ __atomic_check_size((mem)); \
typeof ((__typeof (*(mem))) *(mem)) __atg2_oldval = (oldval); \
!__atomic_compare_exchange_n (mem, (void *) &__atg2_oldval, newval, \
1, __ATOMIC_ACQUIRE, \
__ATOMIC_RELAXED); })
#define catomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
atomic_compare_and_exchange_bool_acq (mem, newval, oldval)
/* Store NEWVALUE in *MEM and return the old value. */
#define atomic_exchange_acq(mem, newvalue) \
({ __atomic_check_size((mem)); \
__atomic_exchange_n (mem, newvalue, __ATOMIC_ACQUIRE); })
#define atomic_exchange_rel(mem, newvalue) \
({ __atomic_check_size((mem)); \
__atomic_exchange_n (mem, newvalue, __ATOMIC_RELEASE); })
/* Add VALUE to *MEM and return the old value of *MEM. */
/* The gcc builtin uses load-and-add instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
# define atomic_exchange_and_add_acq(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_add ((mem), (operand), __ATOMIC_ACQUIRE); })
# define atomic_exchange_and_add_rel(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_add ((mem), (operand), __ATOMIC_RELEASE); })
#define catomic_exchange_and_add(mem, value) \
atomic_exchange_and_add (mem, value)
/* Atomically *mem |= mask and return the old value of *mem. */
/* The gcc builtin uses load-and-or instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_or_val(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_or ((mem), (operand), __ATOMIC_ACQUIRE); })
/* Atomically *mem |= mask. */
#define atomic_or(mem, mask) \
do { \
atomic_or_val (mem, mask); \
} while (0)
#define catomic_or(mem, mask) \
atomic_or (mem, mask)
/* Atomically *mem |= 1 << bit and return true if the bit was set in old value
of *mem. */
/* The load-and-or instruction is used on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_bit_test_set(mem, bit) \
({ __typeof (*(mem)) __atg14_old; \
__typeof (mem) __atg14_memp = (mem); \
__typeof (*(mem)) __atg14_mask = ((__typeof (*(mem))) 1 << (bit)); \
__atg14_old = atomic_or_val (__atg14_memp, __atg14_mask); \
__atg14_old & __atg14_mask; })
/* Atomically *mem &= mask and return the old value of *mem. */
/* The gcc builtin uses load-and-and instruction on z196 zarch and higher cpus
instead of a loop with compare-and-swap instruction. */
#define atomic_and_val(mem, operand) \
({ __atomic_check_size((mem)); \
__atomic_fetch_and ((mem), (operand), __ATOMIC_ACQUIRE); })
/* Atomically *mem &= mask. */
#define atomic_and(mem, mask) \
do { \
atomic_and_val (mem, mask); \
} while (0)
#define catomic_and(mem, mask) \
atomic_and(mem, mask)
|